This invention relates to an apparatus for filtering metallurgical slag. More particularly, this invention relates to a new and improved filtering drum used in conjunction with a metallurgical slag filtering apparatus. The general type of filtering apparatus to which this invention is directed is disclosed in my earlier U.S. Pat. No. 4,204,855, of which all of the disclosure is incorporated herein by reference. This application presents an improved drum construction for the filtering apparatus of U.S. Pat. No. 4,204,855. Other improved features are disclosed in my co-pending U.S. Applications Ser. Nos. 578,816 and 578,818 being filed simultaneously herewith, all of the contents of which are incorporated herein by reference thereto.
The filtration apparatus of U.S. Pat. No. 4,204,855 generally comprises a substantially horizontal rotary drum having filtering screens or foraminous walls along the outside surface thereof and being provided with internal vanes along the inside surface thereof for conveying metallurgical granulated slag material upwardly. Thereafter, the filtered slag falls freely onto a conveyer belt passing longitudinally through the drum. A filtering apparatus of this type will also include a feed channel through which the pulp, i.e., granulated slag and water, is fed into the drum.
The present invention presents an improved drum structure which reduces or prevents the filtering water of one internal vane from falling onto the filtered slag of an adjacent vane on the "downstream" side (i.e. downstream in the direction of the flow of filtered water); which improves damage to the filtration screen around the rotary drum from loose slag; which improves the efficiency of filling and draining of the vanes: and, which improves structural support of the filtering drum by the internal vanes.